The present study used a new assessment technique, the story-generation task, to examine students' understanding of subtraction scenes. The students from four grade levels (110 first-, 107 third-, 110 fourth- and 119 sixth-graders) generated stories under the constraints provided by a picture (representing Change, Combine or Compare scene) and a number sentence. The results showed that the Change scene was the most intuitive, and the students tended to reinterpret Combine and Compare scenes as a form of Change scene, even when they understood that the identity of the objects in the Combine and the Compare scenes was different. The number of students generating correct stories for the Combine scene increased through the elementary school grades while for the Compare scene the number of students generating correct stories remained fairly constant from Grade 3 to Grade 6. This study also examined students' exposure to subtraction scenes in mathematics textbooks and discussed educational implications for supporting students' understanding of subtraction scenes. (Contains 7 tables.)